which temperature?

Low-temperature soldering is not a guarantee for safety and often it is the other way around. Most components get damaged when exposed to any form of heat for a prolonged period. A soldering iron get very hot and can damage those components easily. It might sound awkward, but a high temperature is preferred as long as you can keep the time of exposure to this heat to a minimum. It is all about temperature and speed (precision).

I generally would use thin wiring (like wire-wrap) and tin the end. Try to keep the exposed part of the wire short.

You don't necessarily need to also solder the pad, but you could... but be gentle, since tinning a pad means long exposure to heat if done incorrectly.

Hold the wire in place and just gently touch it. Use some tape nearby if you can't manage to hold it, but NOT preferred since it invites people to use more time than needed.

Keep it all under a second! If you couldn't get the solder to flow in that time, try a little longer... But never longer than 3 seconds! Even components like LED's and transistors can get broken when exposed to heat for more than 3 seconds.